1. Field of the Invention
This invention relates to printing press cylinders, particularly to the adaptation of cylinders originally designed for employment with a printing blanket lock-up device to make them suitable for use with adhesively-securable printing blankets.
2. Discussion of the Prior Art
A common means for securing an offset printing blanket onto a press cylinder employs a tensioning `lock-up` device located within the cylinder body. The device is located in an axially elongate cavity extending into the cylinder body from the cylinder surface. The presence of this device causes a corresponding gap in the usable printing area of the cylinder and furthermore tends to promote undesirable vibration during operation of the printing press, especially at high-speed printing.
Recent developments in printing blankets promote the feasibility of employing a blanket secured to a printing cylinder by adhesive means. New cylinders for such blankets accordingly have a continuous unbroken surface, thereby increasing the usable printing area of the blanket and minimising potential vibration during running of the press.
However, printing cylinders, especially large cylinders of web-feed offset printing presses such as those used in the newspaper and magazine printing industry, are expensive and consequently substitution of a lock-up type of cylinder by a new continuous-surface cylinder is hampered by the entailed cost.
Also, the dismantling and reassembly of a press required for substitution of a printing cylinder is of high concern in the newspaper and magazine printing industry where a long down-time of the press could be highly detrimental to meeting distribution deadlines.